Computer systems are becoming increasingly pervasive in our society, including everything from small handheld electronic devices, such as personal digital data assistants and cellular phones, to application-specific electronic components, such as set-top boxes and other consumer electronics, to medium-sized mobile and desktop systems to large workstations and servers. With deployment of wireless technology, the battery life became very critical characteristic of mobile systems.
To provide more powerful computer systems for consumers, designers strive to continually increase the operating speed of the processor. A by-product of increasing processor speed is an increase in the amount of power consumed by the processor. The increased system power consumption result in need for bigger thermal/cooling system, bigger power delivery system and reducing battery life.
One approach to reducing power consumption of a computer system is based on a Display Power Management System (DPMS) protocol. DPMS is used to selectively shut down parts of the computer system's video display circuitry after a period of inactivity. With a motherboard and a display that support DPMS, power consumption by the computer system, especially by the display may be greatly reduced. The motherboards that support DPMS often have a BIOS (basic input/output system) setting to enable the power consumption option. The BIOS setting controls a length of time the system must be idle (i.e., no activity detected from the user) for the display to be powered off.
The length of the idle time may be specified in minutes or hours, or it may be set to “Disabled” or “Never”. The computer system then tries to detect user's activity during the idle time. User's activities may include, for example, pressing of a key on a keyboard, movement of a mouse, etc. After no activity is detected during the idle time and at expiration of the idle time, the computer system sends appropriate control signals to the display to power off the display. When the display is powered off and the system detects user's activity, the system sends appropriate control signals to power on the display.
Another approach to power management is by setting user's preference using the operating system or application software. For example, power to the display can be managed by setting a power off option in a power management properties menu to a certain fixed expiration value. The expiration value may be set to any value provided in a pop-up window ranging from 1 minute to “never”. The expiration value is static and remains the same until another value is selected. FIG. 1 illustrates a prior art example of a pop-up window used to specify power management preferences. As illustrated in FIG. 1, power can be managed by setting user's preference to turn off monitor, hard disks and to put the system in standby mode.